Prove or disprove each of the following statements:
a. if p is prime and p divides (a^2 + b^2) and p divides (c^2 + d^2), then p divides (a^2 - c^2).
b. if p is prime and p divides (a^2 + b^2) and p divides (c^2 + d^2), then p divides (a^2 + c^2).
c. If p is prime and p divides a and p divides (a^2 + b^2), then p divides b.
help plz..dont know where to start..
No, that's what we assumed in the first place. We also assumed that p divides a.that would imply that p divides a^2 + b^2
In the last post I showed you that from these assumptions follows that p divides .
The definition of prime-numbers gives you that p divides b.